Molded chamber structures are increasingly taking the place of concrete structures for use in leaching fields or to gather stormwater run off. Molded chamber structures provide a number of distinct advantages over traditional concrete tanks. For example, concrete tanks are extremely heavy requiring heavy construction equipment to put them in place. In leaching fields and stormwater collection systems, the gravel used in constructing them is difficult to work with and expensive. It also tends to settle and reduces the overall volume of the trench by as much as 75%.
Attempts have been made to overcome the limitations that are attendant upon the use of traditional septic systems. U.S. Pat. No. 5,087,151 to DiTullio (“the '151 patent”), which represents one such attempt, discloses a drainage and leaching field system comprising vacuum-molded polyethylene chambers that are designed to be connected and locked together in an end-to-end fashion. The chambers comprise a series of pre-molded polyethylene bodies with an arch-shaped configuration having upstanding ribs running transverse to the length of the chamber. The ribs provide compressive strength to the chamber so as to inhibit crushing of the chamber by the weight of earth under which it is buried, as well as the weight of persons, vehicles, etc. which pass over the buried chamber. The rib at an end portion of the chambers is provided slightly smaller than the remaining ribs so that to connect the chambers to one another in an end-to-end fashion, one need simply position the first rib of one chamber over the slightly smaller rib on a second chamber. This may be referred to as an overlapping rib connection. The chambers are typically positioned in a trench on top of a bed of materials that facilitates the flow of fluid into the earth.
While the drainage and leaching field system disclosed in the '151 patent provides numerous benefits over traditional systems, including the provision of a lightweight, easy to install and structurally sound system, the system disclosed in the '151 has been improved upon, which improvements form the basis of the present invention. More specifically, it has been recognized that it is desirable to increase the flow of effluent or stormwater from chamber to chamber. For example, it is known to connect chambers in an end-to-end fashion as disclosed in the '151 patent, thereby providing for the free flow of fluid along that particular row of connected chambers. However, each separate row of chambers has typically been connected to one or more adjoining rows of chambers by relatively small diameter pipe. While the chambers themselves are relatively large to accommodate a large volume of fluid, the pipes interconnecting the different rows of chambers restrict the free flow of fluid throughout the field. In addition, traditionally the interconnecting pipes have been positioned relatively high on the chambers. This means that fluid flow between the chambers will not occur until the fluid level rises at least to the level of the interconnecting pipe. This is undesirable because the fluid is not uniformly distributed throughout the field but instead is maintained generally at the end where the input pipe is located. Another problem with this configuration is that fluid “falling” out of the interconnecting pipe to the floor into the next row of chambers, has a tendency to undermine the base that the chamber sits on creating a situation in which the system may begin to sink.
Another problem with the interconnecting pipes is that any penetration of the side walls of the chambers has traditionally caused an unacceptable weakening in the chamber. Accordingly, in order to maintain the structural integrity of the chamber, interconnecting pipes have traditionally been restricted to entering the ends of the chamber rows. However, depending upon the configuration of the jobsite, this is not always convenient or even possible.
Therefore, what is desired is a system that facilitates the generally even distribution of fluid throughout a drain field or leaching field using molded chamber structures.
It is further desired to provide a system that facilitates the even distribution of fluid throughout a drain field or leaching field while at the same time not reducing the structural integrity of the molded chamber structures.
It is still further desired to provide a system that facilitates the even distribution of fluid throughout a drain field or leaching field while at the same time reduces or substantially eliminates any undermining of and/or damage to the bed upon which the molded chamber structures are positioned.
It is yet further desired to provide a drain field or leaching field system utilizing molded chamber structures that allows for increased variability in the layout and positioning of the molded chamber structures.